IL4 and asthma: Transgenic mice with a dominant-negative mutant of GATA3 display decreased expression level of Th2 cytokines IL-4, IL-5, and IL-13, along with attenuated asthma symptoms, such as airway eosinophilia, mucus production, and IgE synthesis [18], supporting a potentially causal effect of GATA3 on asthma risks.